Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a turbine blade assembly for producing power. Combustors often operate at high temperatures that may exceed 2,500 degrees Fahrenheit. Typical turbine combustor configurations expose turbine vane and blade assemblies, to these high temperatures. As a result, turbine airfoils, such as turbine vanes and blades must be made of materials capable of withstanding such high temperatures. In addition, turbine airfoils often contain internal cooling systems for prolonging the life of the airfoils and reducing the likelihood of failure as a result of excessive temperatures.
Typically, turbine airfoils, such as turbine vanes are formed from an elongated portion having one end configured to be coupled to an outer shroud vane carrier and an opposite end configured to be movably coupled to an inner shroud. The airfoil is ordinarily composed of a leading edge, a trailing edge, a suction side, and a pressure side. The inner aspects of most turbine airfoils typically contain an intricate maze of cooling circuits forming a cooling system. The cooling circuits in the airfoils receive air from the compressor of the turbine engine and pass the air through the ends of the vane adapted to be coupled to the vane carrier. The cooling circuits often include multiple flow paths that are designed to remove heat from the turbine airfoil. At least some of the air passing through these cooling circuits is exhausted through orifices in the leading edge, trailing edge, suction side, and pressure side of the airfoil.
Composite airfoils have been developed for use in turbine engines. Composite airfoils are often constructed as laminate layers formed from high strength fibers woven into cloth that is saturated with ceramic matrix materials. The multiple laminate layers are stacked, compacted to the desired thickness, dried, and fired to achieve the desired structural properties. The laminates have desirable in-plane structural properties but significantly less strength in the through plane direction. Thus, laminates are often not capable of absorbing tensile forces that are encountered in a turbine engine environment. Rather, laminates often are damaged by tensile forces during normal engine operation. Thus, a need exists for a system for structurally supporting a composite turbine airfoil.